Unbreak x86_64-pc-solaris2.1[01], it IS 64-bits too.  Without this,
libtool thinks the linker is called ld_sol2.

--- configure
+++ configure
@@ -1383,7 +1383,7 @@
       case $lt_cv_prog_gnu_ld in
       yes*)
         case $host in
-        i?86-*-solaris*)
+        i?86-*-solaris*|x86_64-*-solaris*)
           LD="${LD-ld} -m elf_x86_64"
           ;;
         sparc*-*-solaris*)
